  //Feel free to use this code.
  //Please be respectful by acknowledging the author in the code if you use or modify it.
  //Author: Bruce Allen
  //Date: 23/07/09
  
  //Digital pin 7 for reading in the pulse width from the MaxSonar device.
  //This variable is a constant because the pin will not change throughout execution of this code.
  const int pwPin = 7; 
  //variables needed to store values
  long pulse, inches, cm;
  void setup() {
    //This opens up a serial connection to shoot the results back to the PC console
    Serial.begin(9600);
  }
  void loop() {
    pinMode(pwPin, INPUT);
      //Used to read in the pulse that is being sent by the MaxSonar device.
    //Pulse Width representation with a scale factor of 147 uS per Inch.
  
    pulse = pulseIn(pwPin, HIGH);
    //147uS per inch
    inches = pulse/147;
    //change inches to centimetres
    cm = inches * 2.54;
    Serial.print(inches);
    Serial.print("in, ");
    Serial.print(cm);
    Serial.print("cm");
    Serial.println();
    delay(500);
  }
